The SmartMedia™ digital data storage card (also known as a “Solid State Floppy Disk Card” (SSFDC)) is a removable data storage medium developed in recent years to store data in various portable electronic devices, such as digital cameras, digital camcorders, personal digital assistants (PDAs), digital audio players, cellular telephones, pagers, etc. Several manufacturers have independently developed versions of this removable storage medium that conform to the SmartMedia™ specifications with respect to its physical size, shape, and pin assignments. In addition to different versions developed by manufacturers, SmartMedia™ storage devices have been developed in packages comprising different amounts of storage capacity. Currently, a range of storage capacities from 2 megabytes (MB) to 128MB is available, with anticipation of even greater storage capacities in the future.
Since a consumer may choose from a number of different manufacturers and storage capacities of SmartMedia™ storage devices for use in the consumer's electronic device, the SmartMedia™ specifications provide a way to identify the manufacturer and product number. When the electronic device is first turned on, the electronic device initiates what is known as an “ID Read” command. By requesting this command, a controller within the electronic device receives from the SmartMedia™ storage device a “Maker Code Output,” which is indicative of the manufacturer of the memory product, and a “Device Code Output,” which is indicative of the model or product number. This information may be used to determine the type and storage capacity of the storage device.
In order for the controller of the electronic device to initiate the ID Read command, the controller sends command code 90h and address 00h to the SmartMedia™ storage device. Then the controller asserts a read enable signal, and the SmartMedia™ storage device outputs the Maker Code Output to the controller. The controller asserts a read enable signal a second time, and the SmartMedia™ storage device outputs the Device Code Output. As mentioned above, the ID Read command is typically performed when the electronic device is powered up so that the controller can identify the type of SmartMedia™ storage device with which it is dealing. From the manufacturer and model number, the controller may determine the data storage capacity and may also store “revisions” that include instructions for working around known peculiarities of certain SmartMedia™ storage devices.
The conventional ID Read is limited in its use in that only a couple pieces of information can be communicated from the storage device to the electronic device. Furthermore, the Maker Code and Device Code information must be decoded by the electronic device to understand what the codes represent.
SmartMedia™ typically utilizes NAND flash memory chips to store data. However, as alternatives to NAND flash memory are developed to accommodate controller functionality, which is absent from NAND flash, a need arises to allow for more communication between the storage device and the controller. With new types of memory being developed, a need arises for an exchange of information relating to new configuration parameters. Furthermore, the prior art is not capable of communicating a sufficient number of parameters to account for various operating and environmental conditions, and for updating parameters when conditions change.